在截至9月底的12个月中，就业成本上涨了2.8％，略低于截止上一季度末的一年。
比较结构要先确定比较对象，本题比较对象是状语，但是此处主语不能省略，易有歧义
1) 比较结构中,如果省略后会对省略结构造成歧义,则不能省略
2) 替代原则: 前面出现过的动词,后面只能用do和did代替,或者重复前面出现过的动词.以本题举
例: 前面出现的rose在比较结构后半句中可以用did替代,或者重复rose
(D) lower只能做形容词,不能修饰动词rose; than in the year比较结构表达太模糊,完全可以理解为
than others expected in the year或 than price rose in the year等等，所以补足主谓可以消除歧义

The word "less" is actually an adverb that modifies the verb "rose" here: "employment costs rose... less than they did [in the past] 所以不用过多考虑名词单复数问题
lower只能做形容词,不能修饰动词rose
Higher and lower we use for physical entities
“did”对应“rose” 不能省略

比较的是增长的%, 用less（更少的）而不是lower（更低的）; than + 主语 + 宾语+ 比较的时间段，本题比较对象是状语，但是此处主语不能省略，易有歧义。正确A，错选D， than in the year比较结构表达太模糊,完全可以理解为 than others expected in the year或 than price rose in the year等等，所以补足主谓可以消除歧义

less than 2.8% or ["2.8% is lower than the percent for last quarter]. some uncountable nouns are plural. for instance, "taxes" is a plural noun, but the concept that it represents is uncountable (taxes are not things that you can separate into one, two, three,...)so, you would say my taxes are less than they were last year, not [i]my taxes are fewer than they were last year[i].

错选E
The meaning should be clear: The costs rose by 2.8% this past year; in the previous year, they rose by more than 2.8%. So, this year, they rose less than they did last year.
"Lower" and "greater" can't be used to compare actions.不能用于动作的比较
lower只能做形容词,不能修饰动词rose;
high/low 不能修饰动作，只能修饰名词。more/less才可以修饰动作，也可以修饰名词。
如果要用lower 需要是 lower than the percentage （they did），而选项中没有percentage或that的指代，可以判断是动作的比较而不是名词的比较。

"lower" cannot be used with countable things.
in general, i can only think of three types of nouns for which you can use "lower" as a quantifier:
1）mathematical quantities (things that can be represented by actual numbers)
2） abstract ideas that aren't necessarily numbers, but that can be thought of as somewhat quantitative
3） things that are literally (= physically) lower than other things

"lower" cannot be used with countable things.
in general, i can only think of three types of nouns for which you can use "lower" as a quantifier:
1）mathematical quantities (things that can be represented by actual numbers)
2） abstract ideas that aren't necessarily numbers, but that can be thought of as somewhat quantitative
3） things that are literally (= physically) lower than other things

这次感觉比较难，句意要理解透才行。首先 B排除，it单复数不对。 slightly less/lower than 去年。如果是lower那么是接的一个number，2.8 percent；less 是指rose less. 带入原句，lower的用法都不对，AC之间选A

注意比较的内容是增长（rose）的百分比，而非 开销， 所以要用副词less，而非形容词lower

(D) lower只能做形容词,不能修饰动词rose; than in the year比较结构表达太模糊,完全可以理解为
than others expected in the year或 than price rose in the year等等，所以补足主谓可以消除歧义

看见than 首先想到比较对象一致的考点；
比较对象：Employment costs rose 2.8 percent 复数主语+动词
所以后面肯定是they did 直接排除BCDE。

另外lower 是形容词不能修饰动词。

未划线部分有两个in, 直接省略导致歧义，因此杀D
costs复数主谓一致，杀B
费用是多少，不是高低，杀DE
平行，杀C

前半部分说的是employment costs的动作，所以要比的是did

less —— sth. rises less than...
lower —— a figure is lower than ...

如果主句前面是用系表结构，是否可以用lower？

MMMMARK

比较的是percent，要用less，和employment costs rose in the year that ... 比较，看清比较对象

比较的是增长的%, 用less而不是lower; than + 主语 + 宾语+ 比较的时间段

比较的动词是rose，lower只能比较名词，故只有A对

比較對象："Employment costs rose 2.8 percent"
--> 代名詞為複數，且動詞為 did

cost是个数值，应该是小于，而不是低于（别用中文思维）